The symbolism could hardly have been more striking as indigenous Awajún member Eduardo Nayap – in suit, tie and colourful Amazonian feather crown – addressed Peru’s new congress last week.

Nayap, a member of President Ollanta Humala’s Nationalist party, was welcoming the chamber’s unanimous approval of a bill requiring prior consultation with indigenous peoples about legislation or infrastructure projects that would affect them or their territories. Humala is expected to sign it into law this week.

In a fractured, multi-ethnic nation where the legacy of the Spanish conquest continues to cast a long shadow over the social realities of the present, the political significance of the new law should not be underestimated. Indeed, Peru’s racial and geographic divisions only deepened over the past half-decade as García imposed his haughty, Lima-centric vision on the country, unforgivably bungling his way to the Bagua massacre.

But now, with the Peruvian economy heavily dependent on the export of primary commodities such as copper, gold, oil and gas, often located on indigenous lands, what concrete difference will the new law make? The first point to grasp is that the legislation does not give communities a right of veto. Instead, it is aimed at generating consensual agreement between them and the state that will allow “development” projects to move ahead. Critically, when consensus is not reached, the Peruvian state will still have the right to impose solutions on a case-by-case basis.

However, most commentators are downplaying this aspect of the legislation, preferring to concentrate on the potential for the new law to allow Peru to resolve its hundreds of “social conflicts” – the term used here for confrontations, often violent, generated when rural communities oppose road-building, mining, drilling, damming or other such interventions on or near their lands.

According to the Defensoría del Pueblo, Peru’s government-funded but independent human rights watchdog, the law establishes that the process of reaching agreement should be “a good faith, intercultural dialogue“, with the representative organisations of the communities’ choosing.

Meanwhile, lawyer Hernán Coronado, of the Amazonian Centre for Anthropology and Practical Application, tells me that the law will require a profound change in the role of the Peruvian state, from previously being a promoter of corporate interests to being a neutral arbiter between the extractive industries and indigenous peoples. Given the massive imbalances in technical and legal knowledge and resources that often exist between the communities and industry, the state may even end up acting as a counterweight to the ambitions of transnational corporations coveting natural resources on indigenous lands, he says.

All this presupposes the political will in Lima to finally allow native communities to control their own economic and social development. And the devil may be in the detail – under Peruvian law, congress will need to elaborate regulations establishing the procedural nitty-gritty of how the consultations regarding an estimated $51bn of already-proposed infrastructure projects, including a series of vast, bitterly resisted hydroelectric dams in the Amazon, will actually work.

But just a month after Peru’s new government took office, the tone and emphasis have changed 180 degrees compared with the previous administration. Earlier this week, Humala’s prime minister, Salomón Lerner Ghitis, announced a new tax on the mining industry’s “surplus earnings” equivalent to more than $1bn a year in additional government revenues. The money will be used for social programmes. Contrast that with García’s government, which had an open-door policy for corporate executives but refused to acknowledge the legitimate expectations of some of Peru’s poorest citizens that national economic development not be at the cost of their families and environment.

In one of García’s parting rhetorical shots as president, he ridiculed the animistic religious beliefs of many Peruvians, inadvertently revealing more about the historic mindset of much of the Lima elite than he did about the cultures of the Andes and Amazon.

Against that backdrop, it would seem churlish to deny the enormous symbolic value of the new law on prior consultation. Nevertheless, after centuries of massacres, slavery and dispossession, Peru’s indigenous peoples will rightly not be dropping their guard any time soon.